This invention relates generally to a combination coolant hood and scalp tourniquet for the prevention of scalp hair loss.
It is known that people afflicted with various forms of cancer may be treated by chemotherapy. A chemical agent placed into the patient's bloodstream is transported to the cells of the body. The uptake of the chemical by the cells in the scalp may have an adverse effect on the functioning of the hair follicles and result in hair loss. While hair loss may be considered primarily to be a minor cosmetic complication, the negative psychological impact on the patient may seriously impede the success of the treatment.
Hair shafts are rooted in hair follicles in the dermis. The hair follicle is a tubular epithelial or membranous cellular tissue which surrounds the lower part of the hair shaft. At the bottom of the follicle is a vascular papilla which supplies the growing basal part of the hair with nourishment. The rate and quantity of the chemotherapeutic agent accepted by hair follicle cells can be reduced if the blood vessels in the papilla are contricted. Constriction of the blood vessels, known as vasoconstriction, can be accomplished by applying physical pressure to the vessels and by subjecting the vessels to temperatures below normal body temperature. The application of pressure with a compress, tightly fastened bandage, or tourniquet, is a well-known method for reducing bleeding by pressure vasoconstrictuion. However, prolonged application of high pressure may permanently damage blood vessels, blocking the flow of blood to the affected area when the pressure is reduced. The application of a tourniquet to the scalp at a sufficiently high pressure to reduce blood flow to the scalp during chemotherapy, and thereby reduce the follicle cell uptake of the chemotherapeutic agent, has been found to be unsatisfactory when used by itself in minimizing or preventing scalp hair loss.
A number of devices are known for inducing vasoconstriction by subjecting the body to subnormal temperatures. This type of vasoconstriction is known as hypothermia. Owens U.S. Pat. No. 1,569,877 discloses a tubular container lined with a waterproof material. The tubular device has a plurality of compartments capable of being filled with ice. The tubular container is tied closed after filling the compartments and then wrapped around the selected body area. Williamson U.S. Pat. No. 1,964,655 also discloses a body cooling device with a single coolant compartment connected to an elastic band having two openings and a belt buckle arrangement. The patient's ears are placed within the openings and the elastic band is buckled to keep the device fixed in its desired location. Henderson U.S. Pat. No. 4,204,543 also discloses a collant bank of elasticized soft textile material with at least one compartment having a pouch for the insertion of individual removable collant containers. Burns U.S. Pat. No. 1,169,123 discloses a head band with a plurality of hot water bottles for alignment with preselected locations around the patient's forehead. The bottles are held in place by strings which also act to adjust the length of the bank and for attachment of a skull icecap.
Other scalp cooling devices are also known. One such device contains compartments permanently enclosing a freezable liquid. The entire device is refrigerated before it is applied to the patient. Another device which is especially designed for scalp hypothermia is constructed of paper. It contains a plurality of compartments containing water and a chemical such as ammonium nitrate. When the compartments are ruptured a cooling gel is produced which remains cool for about 30 to 45 minutes. The device cannot be reused after the compartments are ruptured and the cooling life of the gel may not be suitable for the duration of one treatment. Application of the device to the scalp is time-consuming and difficult. Furthermore, the device must be kept in place during treatment by wrapping an elastic bandage around the device and taping the bandage to keep it from unraveling. The device attempts to reduce hair loss resulting from chemotherapy by means of hypothermic vasoconstriction only. There is no pressure vasoconstriction of the blood vessels in the scalp.